Abstract: A delta signma modulator is programmable to realize a number of different gain settings. A user of the delta sigma modulator (which may be a human or an electronic system) may select a setting among a plurality of available settings. Programmability of gain is realized by selectively controlling the rate of sampling of an analog input relative to the rate of sampling of a reference voltage and/or by controlling interspersing of samples of fixed voltage with the analog input or reference voltage. To effect a positive gain, the rate of sampling of the analog input is selected to the bar larged than that of the rate of sampling of the known reference voltage. Alternatively, or additionally, fixed voltage charge samples are interspersed with the reference. In contrast, to effect a negative gain, the rate of sampling of the analog input is set to be less than the rate of sampling of the reference voltage and/or samples of fixed voltage are interspersed with the analog input.

Abstract: An electronic interface for operating a dot matrix printer to print a pattern appearing on a television screen employs video-type signals incorporating field and line sync signals, digitized image signals representative of dots of information along each raster line and dot pulses for synchronizing the digitized image signals. Upon receipt of a print request, a line address counter is incremented by each line sync pulse. A second counter, which is incremented each time the line address counter reaches a maximum count, has its count set into a horizontal position counter at the beginning of each line scan and is decremented synchronously with the dot pulses. The sequentially received dot information is loaded serially into a shift register and is transferred byte-wise in parallel into a location in a random access memory identified by the count in the line address counter when the horizontal position counter reaches a zero count.